1. Field of the Invention
The present invention relates generally to shielding arrangements for shielding against electromagnetic and radio frequency interference in electronic devices and pertains, more specifically, to shielding arrangements for providing inter-component shielding between plural electronic components on a circuit board, as well as overall shielding of the electronic components.
2. Description of the Related Art
A wide variety of shielding constructions currently is available for use in connection with electronic equipment such as computers, wireless telephones and various other information and communication devices. These devices very often include circuit boards incorporating electronic components which must be shielded against electromagnetic or radio frequency interference. An effective shielding arrangement currently in use in such devices is a metallic shield, known as a xe2x80x9cshielding canxe2x80x9d, including relatively rigid metallic walls having an outer periphery for surrounding the electronic components to be shielded, the walls of the shield being electrically connected, along the outer periphery of the shield, to a grounding circuit to complete the shielding arrangement. In order to enhance the electrical connection between the walls of the shield and the grounding circuit, shielding gaskets have been developed for interposition between the shield and the grounding circuit, the more effective shielding gaskets being constructed of relatively thin flexible sheets of metal extending along the outer periphery of the shield and including a multiplicity of spring contactors integral with the flexible sheet and establishing effective electrical contact between the shield and the grounding circuit for enhanced shielding performance.
Many of the electronic devices outlined above utilize circuit boards incorporating a plurality of electronic components which themselves must be shielded from one another, as well as being shielded by an overall shielding arrangement. Such inter-component shielding usually is achieved by placing individual supplemental shields, or separate xe2x80x9cshielding cansxe2x80x9d, over each individual electronic component and related circuitry, with all of the individual supplemental shields connected to a grounding circuit for effecting the desired individual, inter-component shielding. The use of these separate, individual supplemental shields requires added effort and expense, as well as added bulk and weight, in the construction of electronic devices.
The present invention accomplishes inter-component shielding utilizing a shielding construction which attains the enhanced electrical shielding connection provided by a shielding gasket arrangement, while eliminating the necessity for individual supplemental shields placed at each one of plural electronic components and corresponding related circuitry on a circuit board. As such, the present invention attains several objects and advantages, some of which are summarized as follows: Accomplishes inter-component shielding of plural electronic components and related circuitry incorporated in a circuit board without the necessity for individual, supplemental shields placed at each electronic component; reduces bulk and weight in electronic devices which require inter-component shielding among plural electronic components in the devices; reduces manufacturing complexity in the construction of electronic devices which require inter-component shielding among electronic components in the devices; attains enhanced electrical connections between a shielding arrangement and via grounding circuit in electronic devices; reduces the complexity of design and construction in electronic devices, thereby gaining concomitant reductions in cost; reduces the number and complexity of component parts in electronic devices requiring inter-component shielding; facilitates access to shielded plural electronic components and related circuitry for ease of repair; provides an effective shielding arrangement which includes inter-component shielding in a rugged construction capable of exemplary long-term performance.
The above objects and advantages; as well as further objects and advantages, are attained by the present invention which may be described briefly as a shielding gasket for interposition between a shield housing and a circuit board to shield plural electronic components and related circuitry located on the circuit board within corresponding plural discrete areas bounded by given boundaries including area boundaries extending around each discrete area and perimetric boundaries extending around the plural discrete areas, portions of the shield housing being spaced altitudinally from at least some of the given boundaries at predetermined locations along the given boundaries, the shielding gasket establishing inter-component shielding between the plural electronic components and related circuitry within the area boundaries, as well as enhancing overall perimetric shielding of the plural electronic components within the perimetric boundaries, the shielding gasket comprising: a relatively thin, flexible sheet of electrically conductive material; a pattern of strips extending longitudinally and laterally along the sheet, the pattern of strips corresponding to the given boundaries such that the strips are juxtaposed with the given boundaries when the shielding gasket is interposed between the shield housing and the circuit board; a multiplicity of contactors located along each strip and projecting altitudinally from each strip for establishing contact forces to enhance electrical shielding contact between the shield housing and the circuit board, through the shielding gasket, upon interposition of the shielding gasket between the shield housing and the circuit board; and partitions integral with at least some of the strips and extending altitudinally from the strips at prescribed locations corresponding to the predetermined locations for engaging the shield housing at the predetermined locations to complete the inter-component shielding between the plural electronic components and related circuitry upon interposition of the shielding gasket between the shield housing and the circuit board.
Further, the present invention includes a shielding arrangement for assembly with a circuit board to shield plural electronic components and related circuitry located on the circuit board within corresponding plural discrete areas bounded by given boundaries including area boundaries extending around each discrete area and perimetric boundaries extending around the discrete areas, the shielding arrangement comprising: a shield housing having portions for being spaced altitudinally from at least some of the given boundaries at predetermined locations along the given boundaries; a shielding gasket for establishing inter-component shielding between the plural electronic components and related circuitry within the area boundaries, as well as enhancing overall perimetric shielding of the plural electronic components within the perimetric boundaries, the shielding gasket comprising: a relatively thin, flexible sheet of electrically conductive material; a pattern of strips extending longitudinally and laterally along the sheet, the pattern of strips corresponding to the given boundaries such that the strips are juxtaposed with the given boundaries when the shielding gasket is interposed between the shield housing and the circuit board; a multiplicity of contactors located along each strip and projecting altitudinally from each strip for establishing contact forces to enhance electrical shielding contact between the shield housing and the circuit board, through the shielding gasket, upon assembly of the shielding arrangement with the circuit board; and partitions integral with at least some of the strips and extending altitudinally from the strips at prescribed locations corresponding to the predetermined locations, the partitions engaging the shield housing at the predetermined locations to complete the inter-component shielding between the plural electronic components and related circuitry upon assembly of the shielding arrangement with the circuit board.